Objective To analyze the efficacy of posterior medial mini-incision combined with arthroscopic double SMC knot fixation using high-strength suture in the treatment of posterior cruciate ligament (PCL) avulsion fractures.

Methods Sixty patients with PCL avulsion fractures were selected as the study subjects, and randomly divided into anchor fixation group (treated with anchor fixation, n=30) and high-strength suture fixation group (treated with double SMC knot fixation using high-strength suture, n=30). Follow-up data were recorded for both groups. The fracture healing time, operative time, as well as changes in knee function assessed by the Lysholm score, International Knee Documentation Committee (IKDC) score and knee range of motion before and after treatment were compared between the two groups.

Results The follow-up period for all 60 patients ranged from 6.5 to 22.5 months, with a mean time of (13.50±7.49) months. No patients were lost during follow-up. Four patients in each group showed a weakly positive drawer test, but no restrictions in knee extension were observed. There were no statistically significant differences in postoperative Lysholm scores, IKDC scores and knee range of motion between the two groups (P>0.05). The fracture healing time and operative time in the high-strength suture fixation group were (11.27±0.87)weeks and (53.73±4.67) minutes, respectively, which were significantly shorter than (12.35±1.03) weeks and (64.06±5.13) minutes in the anchor fixation group (P < 0.05).

Conclusion Both posterior medial mini-incision combined with arthroscopic double SMC knot fixation using high-strength suture or anchor fixation are effective in treating PCL avulsion fractures. However, the high-strength suture double SMC knot fixation method exhibits shorter operative time and fracture healing time, as well as lower operative difficulty.